How the F-102 became a night fighter in Vietnam adapted the Convair Delta Dagger’s infrared search/track system for detecting heat sources on the Ho Chi Minh trail, arming it with AIM-4 Falcon missiles and 2.75-inch rockets for precision night strikes. Deployed from 1962 for intercepts, RESCAP rescues, and bomber escorts during Rolling Thunder, it flew versatile missions until 1968 replacement by F-4 Phantoms.
During the early years of the Vietnam War, the century series of fighters would be deployed to act in a variety of roles, before the mass rollout of the F-4 Phantom.
These aircraft – all designs from the early to mid 50s, created to fill gaps realised during the Korean War – held their own during this new conflict in southeast Asia. The F-104 saw minimal action in Vietnam, whereas the F-101 Voodoo and Super Sabre were more extensively deployed, performing a variety of tasks, from recon to combat air patrol. The F-105 Thunderchief, however, would lead the class as the primary strike aircraft before being replaced by the F-4 Phantom.
The F-102 Delta Dagger also saw some action, albeit with far less publicity than its contemporaries. Arguably the most overlooked aircraft from the century series, the F-102 filled a unique set of roles during the conflict. And so today we will take a look at the history of the Delta Dagger and it’s interesting use during the Vietnam War.
BACKGROUND
The Delta Dagger had first emerged in the early 1950s, first flying in 1953, and entering service in 1956 as America’s first dedicated supersonic interceptor.
This period saw a brief but radical alteration to air warfare doctrines. Speed and altitude were now of paramount importance. Both Soviet and American designers alike believed that – in the case of war – the most effective delivery platform for nuclear or conventional weapons would be in the form of supersonic, high altitude capable bombers.
Thus, a mass adoption process began. Increasingly fast bomber aircraft were drawn up, culminating in high altitude supersonic concepts like the American B-70 Valkyrie; a Mach 3+ capable platform.
To escort friendly bombers, and intercept hostile ones, an increasing number of modernised supersonic fighters and interceptors were placed on order. These designs would become known as the Century series of aircraft; the F-100 Super Sabre – a fighter designed to supersede the F-86 – the F-101 Voodoo – a multirole platform – the F-104 Starfighter – a Mach 2 interceptor – and later the F-105 Thunderchief – a more capable Mach 2 fighter bomber.
A lesser-known design would also emerge as part of the series. This would be the F-102 Delta Dagger. Unlike the other designs, the role of the F-102 was not as clearly defined; in its initial prototyping phase the design wasn’t up to the task of supersonic flight. However, redesigns would remedy this.
Capable of Mach 1.25 at altitude, it was slower than several of its contemporaries, while its advanced fire control system – a major selling point at the time – had proven too complex to efficiently produce for the aircraft. Nevertheless, its principal task would be as an interceptor, and it was ordered into service in 1956.
While the Delta Dagger would be supplemented and later replaced in its interceptor role by the F-106 Delta Dart – a heavily redesigned unit based on the Delta Dagger – the aircraft would continue in its service into the 1960s.
OPERATIONS IN VIETNAM
By 1961, America had committed limited but crucial resources to South Vietnam, beginning with the Strategic Hamlet Program, a growing number of advisors from the military and CIA were now on the ground. With the domestic conflict escalating, by 1962 it was decided that the risk of North Vietnamese airstrikes in the south warranted the deployment of American interceptors to the region. That same year, the first F-102s would arrive in Thailand, tasked with intercepting North Vietnamese bombers if the threat presented itself.
Following the Gulf of Tonkin incident in 1964, a full-scale US entry into the war would begin. A huge buildup of US air power in the region would follow, spearheaded by US Navy and Marine squadrons. Among some of the first US aircrews to arrive in Southeast Asia following the incident would be the 509th Fighter Interceptor Squadron, deployed to the Philippines on August 4th, 1964, just two days after the opening engagement in the gulf.
During the opening months of the war, the F-102 would be employed roughly within its intended parameters; on standby as an interceptor if needed. With a self-starting motor, a relatively quick startup time, and internally mounted weapons without safety pins, the aircraft was easy to scramble at a moment’s notice – in the air before most other fighters.
As the conflict escalated, this rapid response time led to the aircraft being employed in a new role; rescue combat air patrol, or RESCAP. Aircraft losses and pilot ejections over enemy territory were not uncommon; high losses were sustained against surface to air missiles. In the case of a successful ejection, time was crucial; while aircrews would stay on station as long as possible, the geographic layout of Vietnam meant on-station patrols were limited by fuel reserves, the availability or speed at which tankers could be sent northwards, and the areas in which tankers felt safe to operate.
Thus, if necessary, the F-102 provided a high-speed response, capable of being on station quickly to provide support. While not intended for air-to-ground tasking, the RESCAP role was considered important in deterring enemy units from encroaching on ejected airmen, as well as providing top cover to rescue helicopters or units on the ground.
In this tasking, Delta Dagger crews were highly effective, with the role largely aligning with the task of interceptor they had been trained for.
As time went on, the F-102 would begin filling a variety of other unique roles.
ESCORT MISSIONS
From 1965 onward, increasingly dangerous bombing operations would be carried out against the North Vietnamese Army. Operation Rolling Thunder would target infrastructure and areas of assumed NVA activity, primarily with the goal of destroying supplies before they could be transported to the Viet Cong in the south.
B-52s would make up the backbone of these bombing missions. Large, slow, and relatively helpless in the case of interception, the B-52 was vulnerable to both surface-to-air missiles and direct interception by MiGs— a realistic threat when striking targets in the north.
During this time, the same vulnerability was felt by F-105 and F-4 Phantom crews on air-to-ground missions; usually ferrying large quantities of munitions northwards with the goal of carpet-bombing enemy positions.
The Dagger would thus supplement other fighters – including the Super Sabre and F-104 – in the role of bomber escort. In this role, only one aircraft would be lost to enemy fire; a single K-13 infrared missile fired from a MiG-21 would impact and destroy a Dagger flying bomber escort on February 3rd 1968. Thirteen other units would be lost in Vietnam, all due to pilot fault or mechanical failure.
By the late 60s, the Delta Dagger’s role as bomber escort remained, although with diminishing scope. Several changes to doctrine improved overall effectiveness and efficiency; improved methods of bomb delivery, as well as the LORAN system, and the introduction of experimental targeting pods, essentially mitigated the need for carpet bombing. Crucially, this meant Phantom crews would be more effectively used over enemy territory in multirole tasking; carrying less air-to-ground ordinance for essentially the same impact, and with less fuel consumption while armed with more effective air-to-air standoff capabilities when self-defence was needed.
This same efficiency translated over to MIGCAP and escort missions, which now were predominately being handled by the F-4 Phantom.
In essence, the Dagger would remain in frontline use, although its employment would steadily decrease as the war went on, culminating in its return to the United States in 1968.
AIR TO GROUND TASKING
However, despite its relatively limited combat record, Dagger pilots would have the opportunity to fill a unique role now and then – the night-time strike missions.
Long before formal US involvement in Vietnam began, Northern forces had successfully resupplied southern guerrilla fighters via a complex network of tracks in western Vietnam, Cambodia, and Laos, known as the Ho Chi Minh trail.
Following the start of the war, bombing missions targeting the Ho Chi Minh trail would be a chief priority. The most efficient of these were precision strikes carried out by strike aircraft; Super Sabres, F-105s, and Phantoms. This would continue throughout the war, although limited to daytime strikes.
Early in the conflict, the Viet Cong had shifted most of its mobilising activity to nighttime, oftentimes using fire lamps rather than headlights to ferry trucks up and down the trail to remain as hidden as possible. B-52s, Phantoms, and others would fly nighttime bombing missions targeting the trail, however these would be imprecise, essentially carpet bombing areas of reported activity.
In fact, a true remedy to this problem wouldn’t emerge until 1968, with the introduction of the first AC-130 gunships. Equipped with infrared cameras and a magnetic anomaly detector, these provided consistent and reliable precision capability at night.
During the interim, other workarounds were employed. Iroquois equipped with searchlights or carbon monoxide detectors – known as ‘sniffers’ – flew night raids on occasions.
Dagger crews would be called up for similar tasking.
A unique feature of the aircraft was its infrared search and track system. While archaic by modern standards, the system did allow for acquisition of heat sources at night, a capability uncommon during the mid 1960s. Effectiveness was noted as being average; heat sources would need to be substantial, or nights sufficiently cold to produce the necessary temperature contrast for acquisition.
With zero training for air-to-ground sorties – let alone the task they were now filling – Dagger crews would fly night missions with mixed results.
With only two native weapon systems available for the platform; 2.75-inch rockets and the archaic AIM-4 infrared air-to-air missile, crews were reported to at one point have found a workaround for accurate night time targeting. If heat sources were sufficient to be located via the search and track system, the AIM-4 Falcon could be fired into the vicinity, tracking the heat source on the ground.
On several occasions, the creative employment of the AIM-4 as an air-to-ground weapon was reported, thus effectively making the Dagger one of the first platforms capable of precision strikes at night, albeit with serious limitations.
Over time the Dagger would be called up for conventional air-to-ground tasking during the day, albeit in a limited capacity, likely using rockets.
Given the drawbacks, and the introduction of more effective systems for both day and night precision strike, the F-102 would slowly be pulled back from these rather limited tasks, until its eventual return to the US.
CONCLUSION
Following Vietnam, the Dagger found itself at the end of its practical use. In 1973, the first aircraft were converted into full scale aerial targets (or FSATs), flown as drones for target practice. Before that, 75 units had been sold off to foreign buyers; 25 to the Hellenic Air Force, and 50 to the Turkish Air Force.
Interestingly, both sides would employ the type against one another during the 1974 Turkish invasion of Cyprus, with both sides claiming either victories or losses with the Dagger. Both sides would retire the Dagger in 1979, marking a rather short service life.
In the US, the aircraft would be retired in 1976, marking the end of its long but strange career.
With only two real weapons at hand, it had been intended solely for use as an interceptor, only to be outdone by the more capable F-106. With 1000 units produced, the F-102 was readily available, but had no real purpose it excelled at. Nevertheless, with ingenuity and versatility from pilots and planners, the aircraft would be pushed beyond its limit to utilise its unique strength; infrared search and track, making it perhaps the first easily employable precision night strike fighter.
Among the many pilots to have flown the aircraft include George W Bush, who flew the type between 1970 and 1972 in the National Guard.
Today the Dagger remains probably the most overlooked of the century series aircraft, and a largely forgotten design overall, thanks in large part to its inconsistent career and limited capabilities. Nonetheless, thanks in no small part to the great skill of its pilots, the reputation of the Dagger has lived on through its unique combat experience in Vietnam.
